Ford Focus RS / ST Performance Oil Filter by K&NReplace the oil filter on your Ford Focus RS or ST with K&N's performance oil filter and protect your motor during spirited and track driving. K&N oil filters have been originally developed for demanding automotive race applications that require high oil flow with superb cleaning capabilities. Given the nature of our Ford's it is important to use only the highest of quality parts. K&N oil filters are also easily wrenched-off with a standard tool.

K&N performance oil filters use resin impregnated cellulose filter media which allows for higher flow rates while providing outstanding filtration. Flow rates are important during race applications because oil needs to travel quickly during high RPM applications; so the k&N filter media helps this process by preventing loss of oil pressure through out the system.